With multiple versions of Windows 7 available to buy depending on your needs, which version should you be opting for when it comes to upgrading or starting afresh? Do you really need to opt for the Ultimate edition or will the Starter version do you? Let's try and navigate you through the minefield matrix of the editions likely to be most relevant to you.

As the name suggests this is the starter option for the OS. It's also the edition that is likely to come pre-installed on a netbook if you buy one with Windows 7. You can't actually buy this on its own. 

While many have already proved that you can in fact run the full Ultimate package on netbooks, this is the recommended choice as it's not as feature rich and therefore power heavy.

While you will get most of the core functions (it's not just a browser in a box) you will also miss out as well. Annoyingly you don't get multiple monitor support, something that given the small size of netbook screens we would have thought would be a must, and you won't be able to jazz up your wallpaper either. There is no Aero support, or multi-touch, while Media Center isn't included either. There is no XP mode, no Desktop Windows Manager or Remote Desktop support.

That doesn't mean you are buying a crippled system. You still get most of the new interface features like the improved taskbar and Snap features. You've just got to remember, Starter really does mean starter.

Only available pre-installed

Home Premium is the version you will most likely end up with if you are planning on using Windows 7 in the home rather than in the office. Forgetting Windows 7 Starter edition for a moment and Home Basic (which isn't available in the UK), it is the entry-level option to the OS. Here you do get multiple monitor support, you do get user switching, you do get customisation options, you do get Desktop Windows Manager and Windows Media Center Support.

You also get Aero, Remote Media streaming via Media Player and 32-bit and 64-bit versions if that's what you're interested in.

You won't get an encrypting file system, you won't get Remote Desktop support, you won't get Windows XP mode and a bunch of boring enterprise features that the average home user won't use anyway.

UK: £89.99 US: $119.99

Aimed at the "Professional" whoever that might be, Windows 7 Professional features all the above but includes Windows XP mode and Remote Desktop functionality. It's still not got everything, but for most will be enough to enjoy a full Windows 7 experience. Key bonuses here are Domain Join, a system that lets you connect to a business domain so you can share files, access data and Backup and Restore. While you can run Backup and Restore on the Home Premium options, here you can opt to backup to a network rather than just a hard drive plugged into the computer.

UK: £148.00 US: $199.99

Yep, as the name suggests this comes with everything that you can think of, ticking all the boxes in Microsoft's comparison chart. XP Mode, Virtual hard disk booting, Multilingual support for when you fancy operating your computer in French and Windows Server support - yippee.

Key reasons to get this edition over everything else are three-fold. The first is because you feel the need to own the "I've got it all" package, the other two, which are probably more valid reasons are BitLocker and Virtual hard disk booting. BitLocker allows you to put a virtual lock on your data in case it gets lost or stolen. You've probably already seen software like this on external hard drives from people like HP, Seagate and Buffalo, and now you can do it here on your main drive. Virtual hard disk booting is a bit like Boot Camp on the Mac allowing you to boot different operating systems if you fancy loading up Windows Vista, Linux or something random.

UK: £159.99 US: $219.99